Chemical analysis and missing element trials with Sorghum vulgare L. showed that three Panamanian soils, representative of three great soil groups, were deficient in both nitrogen (N) and phosphorus (P). When a greenhouse trial was undertaken to test the response of Cajanus cajan to rhizobial inoculation, N and P fertilization in these soils, no response was obtained in either the Río Hato or Los Santos soils. There was a definite response to P and a slight response to inoculation in the Pacora soil, which had the poorest fertility level. N applications depressed nodulation.

This paper reviews the experimental basis for the lectin-recognition hypothesis and considers ways in which the host/Rhizobium interaction might be manipulated to enhance the benefits of symbiotic nitrogen fixation in the tropics.

Biological nitrogen (N2) fixation in both free-living and symbiotic organisms is an energy-requiring process dependent upon a supply of carbon and energy. In this paper the energy costs for N2 fixation and nodule respiration in symbiotic systems are compared with those of free-living N2-fixing systems, with the theoretical energy requierement for N2 fixation, and with the cost of utilization of combined N.

Rapport over de bodemgesteldheid van het toekomstige ruilverkavelingsgebied Sauwerd. Toegevoegd is een geschiktheidsbeoordeling voor moderne weidebouw zowel bij de huidige toestand als bij een verbeterde ontwatering